1use crate::{
2 point, px, size, Bounds, DevicePixels, Font, FontFeatures, FontId, FontMetrics, FontRun,
3 FontStyle, FontWeight, GlyphId, LineLayout, Pixels, PlatformTextSystem, Point,
4 RenderGlyphParams, Result, ShapedGlyph, ShapedRun, SharedString, Size, SUBPIXEL_VARIANTS,
5};
6use anyhow::anyhow;
7use cocoa::appkit::{CGFloat, CGPoint};
8use collections::{BTreeSet, HashMap};
9use core_foundation::{
10 array::CFIndex,
11 attributed_string::{CFAttributedStringRef, CFMutableAttributedString},
12 base::{CFRange, TCFType},
13 number::CFNumber,
14 string::CFString,
15};
16use core_graphics::{
17 base::{kCGImageAlphaPremultipliedLast, CGGlyph},
18 color_space::CGColorSpace,
19 context::CGContext,
20};
21use core_text::{
22 font::CTFont,
23 font_descriptor::{
24 kCTFontSlantTrait, kCTFontSymbolicTrait, kCTFontWeightTrait, kCTFontWidthTrait,
25 },
26 line::CTLine,
27 string_attributes::kCTFontAttributeName,
28};
29use font_kit::{
30 font::Font as FontKitFont,
31 handle::Handle,
32 hinting::HintingOptions,
33 metrics::Metrics,
34 properties::{Style as FontkitStyle, Weight as FontkitWeight},
35 source::SystemSource,
36 sources::mem::MemSource,
37};
38use parking_lot::{RwLock, RwLockUpgradableReadGuard};
39use pathfinder_geometry::{
40 rect::{RectF, RectI},
41 transform2d::Transform2F,
42 vector::{Vector2F, Vector2I},
43};
44use smallvec::SmallVec;
45use std::{borrow::Cow, char, cmp, convert::TryFrom, ffi::c_void, sync::Arc};
46
47use super::open_type;
48
49#[allow(non_upper_case_globals)]
50const kCGImageAlphaOnly: u32 = 7;
51
52pub(crate) struct MacTextSystem(RwLock<MacTextSystemState>);
53
54struct MacTextSystemState {
55 memory_source: MemSource,
56 system_source: SystemSource,
57 fonts: Vec<FontKitFont>,
58 font_selections: HashMap<Font, FontId>,
59 font_ids_by_postscript_name: HashMap<String, FontId>,
60 font_ids_by_family_name: HashMap<SharedString, SmallVec<[FontId; 4]>>,
61 postscript_names_by_font_id: HashMap<FontId, String>,
62}
63
64impl MacTextSystem {
65 pub(crate) fn new() -> Self {
66 Self(RwLock::new(MacTextSystemState {
67 memory_source: MemSource::empty(),
68 system_source: SystemSource::new(),
69 fonts: Vec::new(),
70 font_selections: HashMap::default(),
71 font_ids_by_postscript_name: HashMap::default(),
72 font_ids_by_family_name: HashMap::default(),
73 postscript_names_by_font_id: HashMap::default(),
74 }))
75 }
76}
77
78impl Default for MacTextSystem {
79 fn default() -> Self {
80 Self::new()
81 }
82}
83
84impl PlatformTextSystem for MacTextSystem {
85 fn add_fonts(&self, fonts: Vec<Cow<'static, [u8]>>) -> Result<()> {
86 self.0.write().add_fonts(fonts)
87 }
88
89 fn all_font_names(&self) -> Vec<String> {
90 let collection = core_text::font_collection::create_for_all_families();
91 let Some(descriptors) = collection.get_descriptors() else {
92 return Vec::new();
93 };
94 let mut names = BTreeSet::new();
95 for descriptor in descriptors.into_iter() {
96 names.extend(lenient_font_attributes::family_name(&descriptor));
97 }
98 if let Ok(fonts_in_memory) = self.0.read().memory_source.all_families() {
99 names.extend(fonts_in_memory);
100 }
101 names.into_iter().collect()
102 }
103
104 fn all_font_families(&self) -> Vec<String> {
105 self.0
106 .read()
107 .system_source
108 .all_families()
109 .expect("core text should never return an error")
110 }
111
112 fn font_id(&self, font: &Font) -> Result<FontId> {
113 let lock = self.0.upgradable_read();
114 if let Some(font_id) = lock.font_selections.get(font) {
115 Ok(*font_id)
116 } else {
117 let mut lock = RwLockUpgradableReadGuard::upgrade(lock);
118 let candidates = if let Some(font_ids) = lock.font_ids_by_family_name.get(&font.family)
119 {
120 font_ids.as_slice()
121 } else {
122 let font_ids = lock.load_family(&font.family, font.features)?;
123 lock.font_ids_by_family_name
124 .insert(font.family.clone(), font_ids);
125 lock.font_ids_by_family_name[&font.family].as_ref()
126 };
127
128 let candidate_properties = candidates
129 .iter()
130 .map(|font_id| lock.fonts[font_id.0].properties())
131 .collect::<SmallVec<[_; 4]>>();
132
133 let ix = font_kit::matching::find_best_match(
134 &candidate_properties,
135 &font_kit::properties::Properties {
136 style: font.style.into(),
137 weight: font.weight.into(),
138 stretch: Default::default(),
139 },
140 )?;
141
142 let font_id = candidates[ix];
143 lock.font_selections.insert(font.clone(), font_id);
144 Ok(font_id)
145 }
146 }
147
148 fn font_metrics(&self, font_id: FontId) -> FontMetrics {
149 self.0.read().fonts[font_id.0].metrics().into()
150 }
151
152 fn typographic_bounds(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Bounds<f32>> {
153 Ok(self.0.read().fonts[font_id.0]
154 .typographic_bounds(glyph_id.0)?
155 .into())
156 }
157
158 fn advance(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Size<f32>> {
159 self.0.read().advance(font_id, glyph_id)
160 }
161
162 fn glyph_for_char(&self, font_id: FontId, ch: char) -> Option<GlyphId> {
163 self.0.read().glyph_for_char(font_id, ch)
164 }
165
166 fn glyph_raster_bounds(&self, params: &RenderGlyphParams) -> Result<Bounds<DevicePixels>> {
167 self.0.read().raster_bounds(params)
168 }
169
170 fn rasterize_glyph(
171 &self,
172 glyph_id: &RenderGlyphParams,
173 raster_bounds: Bounds<DevicePixels>,
174 ) -> Result<(Size<DevicePixels>, Vec<u8>)> {
175 self.0.read().rasterize_glyph(glyph_id, raster_bounds)
176 }
177
178 fn layout_line(&self, text: &str, font_size: Pixels, font_runs: &[FontRun]) -> LineLayout {
179 self.0.write().layout_line(text, font_size, font_runs)
180 }
181
182 fn wrap_line(
183 &self,
184 text: &str,
185 font_id: FontId,
186 font_size: Pixels,
187 width: Pixels,
188 ) -> Vec<usize> {
189 self.0.read().wrap_line(text, font_id, font_size, width)
190 }
191}
192
193impl MacTextSystemState {
194 fn add_fonts(&mut self, fonts: Vec<Cow<'static, [u8]>>) -> Result<()> {
195 let fonts = fonts
196 .into_iter()
197 .map(|bytes| match bytes {
198 Cow::Borrowed(embedded_font) => {
199 let data_provider = unsafe {
200 core_graphics::data_provider::CGDataProvider::from_slice(embedded_font)
201 };
202 let font = core_graphics::font::CGFont::from_data_provider(data_provider)
203 .map_err(|_| anyhow!("Could not load an embedded font."))?;
204 let font = font_kit::loaders::core_text::Font::from_core_graphics_font(font);
205 Ok(Handle::from_native(&font))
206 }
207 Cow::Owned(bytes) => Ok(Handle::from_memory(Arc::new(bytes), 0)),
208 })
209 .collect::<Result<Vec<_>>>()?;
210 self.memory_source.add_fonts(fonts.into_iter())?;
211 Ok(())
212 }
213
214 fn load_family(
215 &mut self,
216 name: &SharedString,
217 features: FontFeatures,
218 ) -> Result<SmallVec<[FontId; 4]>> {
219 let mut font_ids = SmallVec::new();
220 let family = self
221 .memory_source
222 .select_family_by_name(name.as_ref())
223 .or_else(|_| self.system_source.select_family_by_name(name.as_ref()))?;
224 for font in family.fonts() {
225 let mut font = font.load()?;
226 open_type::apply_features(&mut font, features);
227 let Some(_) = font.glyph_for_char('m') else {
228 continue;
229 };
230 // We've seen a number of panics in production caused by calling font.properties()
231 // which unwraps a downcast to CFNumber. This is an attempt to avoid the panic,
232 // and to try and identify the incalcitrant font.
233 let traits = font.native_font().all_traits();
234 if unsafe {
235 !(traits
236 .get(kCTFontSymbolicTrait)
237 .downcast::<CFNumber>()
238 .is_some()
239 && traits
240 .get(kCTFontWidthTrait)
241 .downcast::<CFNumber>()
242 .is_some()
243 && traits
244 .get(kCTFontWeightTrait)
245 .downcast::<CFNumber>()
246 .is_some()
247 && traits
248 .get(kCTFontSlantTrait)
249 .downcast::<CFNumber>()
250 .is_some())
251 } {
252 log::error!(
253 "Failed to read traits for font {:?}",
254 font.postscript_name().unwrap()
255 );
256 continue;
257 }
258
259 let font_id = FontId(self.fonts.len());
260 font_ids.push(font_id);
261 let postscript_name = font.postscript_name().unwrap();
262 self.font_ids_by_postscript_name
263 .insert(postscript_name.clone(), font_id);
264 self.postscript_names_by_font_id
265 .insert(font_id, postscript_name);
266 self.fonts.push(font);
267 }
268 Ok(font_ids)
269 }
270
271 fn advance(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Size<f32>> {
272 Ok(self.fonts[font_id.0].advance(glyph_id.0)?.into())
273 }
274
275 fn glyph_for_char(&self, font_id: FontId, ch: char) -> Option<GlyphId> {
276 self.fonts[font_id.0].glyph_for_char(ch).map(GlyphId)
277 }
278
279 fn id_for_native_font(&mut self, requested_font: CTFont) -> FontId {
280 let postscript_name = requested_font.postscript_name();
281 if let Some(font_id) = self.font_ids_by_postscript_name.get(&postscript_name) {
282 *font_id
283 } else {
284 let font_id = FontId(self.fonts.len());
285 self.font_ids_by_postscript_name
286 .insert(postscript_name.clone(), font_id);
287 self.postscript_names_by_font_id
288 .insert(font_id, postscript_name);
289 self.fonts
290 .push(font_kit::font::Font::from_core_graphics_font(
291 requested_font.copy_to_CGFont(),
292 ));
293 font_id
294 }
295 }
296
297 fn is_emoji(&self, font_id: FontId) -> bool {
298 self.postscript_names_by_font_id
299 .get(&font_id)
300 .map_or(false, |postscript_name| {
301 postscript_name == "AppleColorEmoji"
302 })
303 }
304
305 fn raster_bounds(&self, params: &RenderGlyphParams) -> Result<Bounds<DevicePixels>> {
306 let font = &self.fonts[params.font_id.0];
307 let scale = Transform2F::from_scale(params.scale_factor);
308 Ok(font
309 .raster_bounds(
310 params.glyph_id.0,
311 params.font_size.into(),
312 scale,
313 HintingOptions::None,
314 font_kit::canvas::RasterizationOptions::GrayscaleAa,
315 )?
316 .into())
317 }
318
319 fn rasterize_glyph(
320 &self,
321 params: &RenderGlyphParams,
322 glyph_bounds: Bounds<DevicePixels>,
323 ) -> Result<(Size<DevicePixels>, Vec<u8>)> {
324 if glyph_bounds.size.width.0 == 0 || glyph_bounds.size.height.0 == 0 {
325 Err(anyhow!("glyph bounds are empty"))
326 } else {
327 // Add an extra pixel when the subpixel variant isn't zero to make room for anti-aliasing.
328 let mut bitmap_size = glyph_bounds.size;
329 if params.subpixel_variant.x > 0 {
330 bitmap_size.width += DevicePixels(1);
331 }
332 if params.subpixel_variant.y > 0 {
333 bitmap_size.height += DevicePixels(1);
334 }
335 let bitmap_size = bitmap_size;
336
337 let mut bytes;
338 let cx;
339 if params.is_emoji {
340 bytes = vec![0; bitmap_size.width.0 as usize * 4 * bitmap_size.height.0 as usize];
341 cx = CGContext::create_bitmap_context(
342 Some(bytes.as_mut_ptr() as *mut _),
343 bitmap_size.width.0 as usize,
344 bitmap_size.height.0 as usize,
345 8,
346 bitmap_size.width.0 as usize * 4,
347 &CGColorSpace::create_device_rgb(),
348 kCGImageAlphaPremultipliedLast,
349 );
350 } else {
351 bytes = vec![0; bitmap_size.width.0 as usize * bitmap_size.height.0 as usize];
352 cx = CGContext::create_bitmap_context(
353 Some(bytes.as_mut_ptr() as *mut _),
354 bitmap_size.width.0 as usize,
355 bitmap_size.height.0 as usize,
356 8,
357 bitmap_size.width.0 as usize,
358 &CGColorSpace::create_device_gray(),
359 kCGImageAlphaOnly,
360 );
361 }
362
363 // Move the origin to bottom left and account for scaling, this
364 // makes drawing text consistent with the font-kit's raster_bounds.
365 cx.translate(
366 -glyph_bounds.origin.x.0 as CGFloat,
367 (glyph_bounds.origin.y.0 + glyph_bounds.size.height.0) as CGFloat,
368 );
369 cx.scale(
370 params.scale_factor as CGFloat,
371 params.scale_factor as CGFloat,
372 );
373
374 let subpixel_shift = params
375 .subpixel_variant
376 .map(|v| v as f32 / SUBPIXEL_VARIANTS as f32);
377 cx.set_allows_font_subpixel_positioning(true);
378 cx.set_should_subpixel_position_fonts(true);
379 cx.set_allows_font_subpixel_quantization(false);
380 cx.set_should_subpixel_quantize_fonts(false);
381 self.fonts[params.font_id.0]
382 .native_font()
383 .clone_with_font_size(f32::from(params.font_size) as CGFloat)
384 .draw_glyphs(
385 &[params.glyph_id.0 as CGGlyph],
386 &[CGPoint::new(
387 (subpixel_shift.x / params.scale_factor) as CGFloat,
388 (subpixel_shift.y / params.scale_factor) as CGFloat,
389 )],
390 cx,
391 );
392
393 if params.is_emoji {
394 // Convert from RGBA with premultiplied alpha to BGRA with straight alpha.
395 for pixel in bytes.chunks_exact_mut(4) {
396 pixel.swap(0, 2);
397 let a = pixel[3] as f32 / 255.;
398 pixel[0] = (pixel[0] as f32 / a) as u8;
399 pixel[1] = (pixel[1] as f32 / a) as u8;
400 pixel[2] = (pixel[2] as f32 / a) as u8;
401 }
402 }
403
404 Ok((bitmap_size, bytes))
405 }
406 }
407
408 fn layout_line(&mut self, text: &str, font_size: Pixels, font_runs: &[FontRun]) -> LineLayout {
409 // Construct the attributed string, converting UTF8 ranges to UTF16 ranges.
410 let mut string = CFMutableAttributedString::new();
411 {
412 string.replace_str(&CFString::new(text), CFRange::init(0, 0));
413 let utf16_line_len = string.char_len() as usize;
414
415 let mut ix_converter = StringIndexConverter::new(text);
416 for run in font_runs {
417 let utf8_end = ix_converter.utf8_ix + run.len;
418 let utf16_start = ix_converter.utf16_ix;
419
420 if utf16_start >= utf16_line_len {
421 break;
422 }
423
424 ix_converter.advance_to_utf8_ix(utf8_end);
425 let utf16_end = cmp::min(ix_converter.utf16_ix, utf16_line_len);
426
427 let cf_range =
428 CFRange::init(utf16_start as isize, (utf16_end - utf16_start) as isize);
429
430 let font: &FontKitFont = &self.fonts[run.font_id.0];
431 unsafe {
432 string.set_attribute(
433 cf_range,
434 kCTFontAttributeName,
435 &font.native_font().clone_with_font_size(font_size.into()),
436 );
437 }
438
439 if utf16_end == utf16_line_len {
440 break;
441 }
442 }
443 }
444
445 // Retrieve the glyphs from the shaped line, converting UTF16 offsets to UTF8 offsets.
446 let line = CTLine::new_with_attributed_string(string.as_concrete_TypeRef());
447
448 let mut runs = Vec::new();
449 for run in line.glyph_runs().into_iter() {
450 let attributes = run.attributes().unwrap();
451 let font = unsafe {
452 attributes
453 .get(kCTFontAttributeName)
454 .downcast::<CTFont>()
455 .unwrap()
456 };
457 let font_id = self.id_for_native_font(font);
458
459 let mut ix_converter = StringIndexConverter::new(text);
460 let mut glyphs = SmallVec::new();
461 for ((glyph_id, position), glyph_utf16_ix) in run
462 .glyphs()
463 .iter()
464 .zip(run.positions().iter())
465 .zip(run.string_indices().iter())
466 {
467 let glyph_utf16_ix = usize::try_from(*glyph_utf16_ix).unwrap();
468 ix_converter.advance_to_utf16_ix(glyph_utf16_ix);
469 glyphs.push(ShapedGlyph {
470 id: GlyphId(*glyph_id as u32),
471 position: point(position.x as f32, position.y as f32).map(px),
472 index: ix_converter.utf8_ix,
473 is_emoji: self.is_emoji(font_id),
474 });
475 }
476
477 runs.push(ShapedRun { font_id, glyphs })
478 }
479
480 let typographic_bounds = line.get_typographic_bounds();
481 LineLayout {
482 runs,
483 font_size,
484 width: typographic_bounds.width.into(),
485 ascent: typographic_bounds.ascent.into(),
486 descent: typographic_bounds.descent.into(),
487 len: text.len(),
488 }
489 }
490
491 fn wrap_line(
492 &self,
493 text: &str,
494 font_id: FontId,
495 font_size: Pixels,
496 width: Pixels,
497 ) -> Vec<usize> {
498 let mut string = CFMutableAttributedString::new();
499 string.replace_str(&CFString::new(text), CFRange::init(0, 0));
500 let cf_range = CFRange::init(0, text.encode_utf16().count() as isize);
501 let font = &self.fonts[font_id.0];
502 unsafe {
503 string.set_attribute(
504 cf_range,
505 kCTFontAttributeName,
506 &font.native_font().clone_with_font_size(font_size.into()),
507 );
508
509 let typesetter = CTTypesetterCreateWithAttributedString(string.as_concrete_TypeRef());
510 let mut ix_converter = StringIndexConverter::new(text);
511 let mut break_indices = Vec::new();
512 while ix_converter.utf8_ix < text.len() {
513 let utf16_len = CTTypesetterSuggestLineBreak(
514 typesetter,
515 ix_converter.utf16_ix as isize,
516 width.into(),
517 ) as usize;
518 ix_converter.advance_to_utf16_ix(ix_converter.utf16_ix + utf16_len);
519 if ix_converter.utf8_ix >= text.len() {
520 break;
521 }
522 break_indices.push(ix_converter.utf8_ix);
523 }
524 break_indices
525 }
526 }
527}
528
529#[derive(Clone)]
530struct StringIndexConverter<'a> {
531 text: &'a str,
532 utf8_ix: usize,
533 utf16_ix: usize,
534}
535
536impl<'a> StringIndexConverter<'a> {
537 fn new(text: &'a str) -> Self {
538 Self {
539 text,
540 utf8_ix: 0,
541 utf16_ix: 0,
542 }
543 }
544
545 fn advance_to_utf8_ix(&mut self, utf8_target: usize) {
546 for (ix, c) in self.text[self.utf8_ix..].char_indices() {
547 if self.utf8_ix + ix >= utf8_target {
548 self.utf8_ix += ix;
549 return;
550 }
551 self.utf16_ix += c.len_utf16();
552 }
553 self.utf8_ix = self.text.len();
554 }
555
556 fn advance_to_utf16_ix(&mut self, utf16_target: usize) {
557 for (ix, c) in self.text[self.utf8_ix..].char_indices() {
558 if self.utf16_ix >= utf16_target {
559 self.utf8_ix += ix;
560 return;
561 }
562 self.utf16_ix += c.len_utf16();
563 }
564 self.utf8_ix = self.text.len();
565 }
566}
567
568#[repr(C)]
569pub(crate) struct __CFTypesetter(c_void);
570
571type CTTypesetterRef = *const __CFTypesetter;
572
573#[link(name = "CoreText", kind = "framework")]
574extern "C" {
575 fn CTTypesetterCreateWithAttributedString(string: CFAttributedStringRef) -> CTTypesetterRef;
576
577 fn CTTypesetterSuggestLineBreak(
578 typesetter: CTTypesetterRef,
579 start_index: CFIndex,
580 width: f64,
581 ) -> CFIndex;
582}
583
584impl From<Metrics> for FontMetrics {
585 fn from(metrics: Metrics) -> Self {
586 FontMetrics {
587 units_per_em: metrics.units_per_em,
588 ascent: metrics.ascent,
589 descent: metrics.descent,
590 line_gap: metrics.line_gap,
591 underline_position: metrics.underline_position,
592 underline_thickness: metrics.underline_thickness,
593 cap_height: metrics.cap_height,
594 x_height: metrics.x_height,
595 bounding_box: metrics.bounding_box.into(),
596 }
597 }
598}
599
600impl From<RectF> for Bounds<f32> {
601 fn from(rect: RectF) -> Self {
602 Bounds {
603 origin: point(rect.origin_x(), rect.origin_y()),
604 size: size(rect.width(), rect.height()),
605 }
606 }
607}
608
609impl From<RectI> for Bounds<DevicePixels> {
610 fn from(rect: RectI) -> Self {
611 Bounds {
612 origin: point(DevicePixels(rect.origin_x()), DevicePixels(rect.origin_y())),
613 size: size(DevicePixels(rect.width()), DevicePixels(rect.height())),
614 }
615 }
616}
617
618impl From<Vector2I> for Size<DevicePixels> {
619 fn from(value: Vector2I) -> Self {
620 size(value.x().into(), value.y().into())
621 }
622}
623
624impl From<RectI> for Bounds<i32> {
625 fn from(rect: RectI) -> Self {
626 Bounds {
627 origin: point(rect.origin_x(), rect.origin_y()),
628 size: size(rect.width(), rect.height()),
629 }
630 }
631}
632
633impl From<Point<u32>> for Vector2I {
634 fn from(size: Point<u32>) -> Self {
635 Vector2I::new(size.x as i32, size.y as i32)
636 }
637}
638
639impl From<Vector2F> for Size<f32> {
640 fn from(vec: Vector2F) -> Self {
641 size(vec.x(), vec.y())
642 }
643}
644
645impl From<FontWeight> for FontkitWeight {
646 fn from(value: FontWeight) -> Self {
647 FontkitWeight(value.0)
648 }
649}
650
651impl From<FontStyle> for FontkitStyle {
652 fn from(style: FontStyle) -> Self {
653 match style {
654 FontStyle::Normal => FontkitStyle::Normal,
655 FontStyle::Italic => FontkitStyle::Italic,
656 FontStyle::Oblique => FontkitStyle::Oblique,
657 }
658 }
659}
660
661// Some fonts may have no attributest despite `core_text` requiring them (and panicking).
662// This is the same version as `core_text` has without `expect` calls.
663mod lenient_font_attributes {
664 use core_foundation::{
665 base::{CFRetain, CFType, TCFType},
666 string::{CFString, CFStringRef},
667 };
668 use core_text::font_descriptor::{
669 kCTFontFamilyNameAttribute, CTFontDescriptor, CTFontDescriptorCopyAttribute,
670 };
671
672 pub fn family_name(descriptor: &CTFontDescriptor) -> Option<String> {
673 unsafe { get_string_attribute(descriptor, kCTFontFamilyNameAttribute) }
674 }
675
676 fn get_string_attribute(
677 descriptor: &CTFontDescriptor,
678 attribute: CFStringRef,
679 ) -> Option<String> {
680 unsafe {
681 let value = CTFontDescriptorCopyAttribute(descriptor.as_concrete_TypeRef(), attribute);
682 if value.is_null() {
683 return None;
684 }
685
686 let value = CFType::wrap_under_create_rule(value);
687 assert!(value.instance_of::<CFString>());
688 let s = wrap_under_get_rule(value.as_CFTypeRef() as CFStringRef);
689 Some(s.to_string())
690 }
691 }
692
693 unsafe fn wrap_under_get_rule(reference: CFStringRef) -> CFString {
694 assert!(!reference.is_null(), "Attempted to create a NULL object.");
695 let reference = CFRetain(reference as *const ::std::os::raw::c_void) as CFStringRef;
696 TCFType::wrap_under_create_rule(reference)
697 }
698}
699
700#[cfg(test)]
701mod tests {
702 use crate::{font, px, FontRun, GlyphId, MacTextSystem, PlatformTextSystem};
703
704 #[test]
705 fn test_wrap_line() {
706 let fonts = MacTextSystem::new();
707 let font_id = fonts.font_id(&font("Helvetica")).unwrap();
708
709 let line = "one two three four five\n";
710 let wrap_boundaries = fonts.wrap_line(line, font_id, px(16.), px(64.0));
711 assert_eq!(wrap_boundaries, &["one two ".len(), "one two three ".len()]);
712
713 let line = "aaa ααα ✋✋✋ 🎉🎉🎉\n";
714 let wrap_boundaries = fonts.wrap_line(line, font_id, px(16.), px(64.0));
715 assert_eq!(
716 wrap_boundaries,
717 &["aaa ααα ".len(), "aaa ααα ✋✋✋ ".len(),]
718 );
719 }
720
721 #[test]
722 fn test_layout_line_bom_char() {
723 let fonts = MacTextSystem::new();
724 let font_id = fonts.font_id(&font("Helvetica")).unwrap();
725 let line = "\u{feff}";
726 let mut style = FontRun {
727 font_id,
728 len: line.len(),
729 };
730
731 let layout = fonts.layout_line(line, px(16.), &[style]);
732 assert_eq!(layout.len, line.len());
733 assert!(layout.runs.is_empty());
734
735 let line = "a\u{feff}b";
736 style.len = line.len();
737 let layout = fonts.layout_line(line, px(16.), &[style]);
738 assert_eq!(layout.len, line.len());
739 assert_eq!(layout.runs.len(), 1);
740 assert_eq!(layout.runs[0].glyphs.len(), 2);
741 assert_eq!(layout.runs[0].glyphs[0].id, GlyphId(68u32)); // a
742 // There's no glyph for \u{feff}
743 assert_eq!(layout.runs[0].glyphs[1].id, GlyphId(69u32)); // b
744 }
745}